A variety of valve timing control devices of the internal combustion engine have been proposed, and as one of the valve timing control devices, Patent Document 1 discloses a vane type valve timing control device. In this device, as is known, a vane rotor is rotatably disposed at a radially inner side of a cylindrical housing. The vane rotor is provided with vanes that extend in a radially outer direction from an outer circumference of a rotor core and partition off a working chamber formed between adjacent two shoes in the housing into a retard working chamber and an advance working chamber. The device is configured so that, by controlling hydraulic pressures of these retard and advance working chambers, a rotation position of the vane rotor relative to the housing is changed, and the valve timing of the engine valve is controlled.
The vane rotor is provided with a small diameter portion and a large diameter portion whose radial direction size is larger than that of the small diameter portion, which are arranged alternately in a circumferential direction of the vane rotor. Then, an accommodation hole that accommodates therein a lock member movably in an axial direction is formed at the large diameter portion of the vane rotor which is thicker in the radial direction. A tip end portion of this lock member is fitted in a lock hole formed on an axial direction side surface of the housing, and then, the rotation position of the vane rotor relative to the housing is restrained at a predetermined lock position.